Pinion bearing preload adjustment

WARNING: This page is about a different car, the 2007 Ford F550 Super Duty and 2007 Ford F450 Super Duty. However, it is still accessible from the selected car via links, so may be relevant.

NOTE: Also refer to the following illustration.

Fig 1: Installing Pinion Bearing Preload Spacer

Courtesy of FORD MOTOR CO.

Fig 2: Measuring Pinion Bearing Preload With Specifications

Courtesy of FORD MOTOR CO.

Adjust the pinion bearing preload by installing a new pinion bearing preload spacer.
- To increase the preload, install a thinner spacer. To decrease the preload, install a thicker spacer.
- The pinion bearing preload spacers are available in sizes from 7.26 to 8.00 mm (0.286 to 0.315 in).
- Always measure the new spacer before installing it.
- On a flat surface, sand the next thicker size spacer with emery cloth to the required thickness to obtain a closer adjustment. Thoroughly wash the spacer to remove the emery cuttings before installation.
- A 0.0254 mm (0.001 in) change in the spacer thickness will change the torque rate approximately 3.3894 N.m (30 lb-in).
- Repeat Measuring pinion bearing preload torque and Pinion bearing preload adjustment in this procedure until the rotational torque is within specifications.